In one conventional data storage arrangement, a redundant array of inexpensive disks (RAID) includes a set of associated data blocks and an associated parity block. Each of the data blocks in the set, and the parity block, is associated with a respective block guard stored in the RAID that includes a respective cyclic redundancy check value. In this conventional data storage arrangement, after one of the data blocks in the set in the RAID is overwritten (e.g., with new user data), first circuitry in the conventional data storage arrangement recalculates the CRC values of the respective data blocks. Thereafter, the corresponding parity block in the RAID is overwritten with new parity data, and the CRC value associated with the parity block is overwritten in the RAID with the CRC value of the new parity data. The new parity data is calculated by second circuitry in the RAID as the result of a logical exclusive-or operation that involves, as operands, of each of the data blocks in the set.
Unfortunately, in this conventional storage arrangement, the operations involved in the verification of the integrity of the data blocks may take an undesirably large amount of time to perform. Additionally, in this conventional arrangement, in order to facilitate the ability of the first circuitry to re-calculate the CRC values of the data blocks prior to the second circuitry calculating the new parity data based on the data blocks, the first circuitry may constitute a processing stage in the input data path of the second circuitry through which the data blocks propagate prior to being input into the second circuitry. Disadvantageously, this may result in the first and second circuitry being more complex than desired.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly, and be defined only as set forth in the accompanying claims.